The Sabin Vaccine Institute is excited to join countries around the world to celebrate World Immunization Week 2013. Vaccination not only is a life saving intervention, according to the World Health Organization’s State of the World's Vaccines and Immunization report,[1] "Immunization - even with the addition of the new, more costly vaccines - remains one of the most cost-effective health interventions."

Diane Coraggio, Sabin Senior Program Officer working with the Pan American Health Organization's ProVac Initiative, explains what this means and why it matters:

Why is it important to determine the cost-effectiveness of a health intervention?

As health sector budgets grow slowly and the menu of health interventions expands, resources are being allocated more prudently and competing options must be considered carefully. Making evidence-based decisions about vaccine introduction now requires economic analysis in addition to analyses of epidemiologic, logistical, and financial data.[2]

What is cost-effectiveness?

Cost-effectiveness is a method of analysis used to weigh the costs and benefits of a policy or intervention and ultimately compare among alternative uses of limited resources. This approach can help determine whether investment in one vaccine achieves greater or lesser health outcomes relative to investment in another vaccine or public health intervention.[3

When is a health intervention considered ‘cost-effective’?

Following the Commission on Macroeconomics and Health, the World Health Organization (WHO) uses per capita Gross Domestic Product (GDP) to obtain the following threshold values for cost-effectiveness:[4]

The cost per DALY averted is:

Highly cost-effective

Less than the GDP per capita

Cost-effective

Between one and three times the GDP per capita

Not cost-effective

More than three times the GDP per capita

Generally speaking, what factors have the greatest impact on cost-effectiveness outcomes?

The parameters most heavily influencing the outcomes of a cost-effectiveness model for a new vaccine introduction can typically be grouped into three main categories: disease burden, program effectiveness, and vaccine costs. The most influential disease burden data includes disease incidence and case fatality. Critical data about program effectiveness includes vaccine efficacy or effectiveness, target population coverage and herd immunity.[5]

What tools are being used to assess cost-effectiveness?

The Pan American Health Organization’s ProVac Initiative[6] is currently using the TRIVAC model, developed jointly by ProVac with the London School of Hygiene and Tropical Medicine, for conducting country-led economic analyses of Hib, pneumococcal conjugate and rotavirus vaccines. TRIVAC is a static cohort model, which integrates disease burden, population data, vaccine coverage, program costs, costs of illness, and health service utilization using a standardized framework to compare the three vaccines. The model has several language options and is pre-populated with country-specific default parameters from international sources, although countries are encouraged to use their own local data whenever possible. [7]

The ProVac Initiative was established by the Pan American Health Organization (PAHO) and has provided support for the evaluation of Haemophilus influenzae type b (Hib), pneumococcal, rotavirus and HPV vaccines in over 14 countries. Due to its success in Latin America and the Caribbean, PAHO received requests to implement ProVac more widely in World Health Organization (WHO) member countries. In response, the Initiative has expanded to provide technical assistance around evaluating the evidence for new vaccine introduction in non-PAHO countries, leading to the formation of the ProVac International Working Group (IWG).

The ProVac IWG is a pilot effort which aims to transfer tools, methods, and lessons learned from the PAHO ProVac Initiative to other WHO regions for the promotion of evidence-based policy and decision making in low and middle income countries. The IWG will conduct selected country-level cost-effectiveness analyses (CEA) on Hib, pneumococcal and rotavirus vaccine introduction using ProVac tools and will hold three regional workshops on ProVac tools and methods for CEA in AFRO, EMRO, and EURO regions.[8], [9]

As a member of the ProVac IWG, the Sabin Vaccine Institute is developing and piloting a strategy for effectively communicating evidence to stakeholders. The outcome will be a guide for countries on how to promote informed, evidence-based decision making related to vaccine introduction.